Rock-drill.



No. 644,998. Patentedflar. 6, I900.

J. McCULLOCH.

ROCK DRILL.

Application filed Sept. 30, 1899.) (No Model.) 2 Sheetsshnet il.

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and the reduction of wear and leakage.

NI'IE STATES PATENT FFICE.

JAMES MccULLocn, OF'ILLOGAN, ENGLAND.

ROCK-DRILL.

fiPECIFIGA'IION forming part of Letters Patent No. 644,998, dated March 6, 1900.

' A plication filed September 30, 1899. Serial No.732,179. (No model.)

To (ZZZ whom, it may concern:

- Be it known that I, JAMES McCULLooH, engineer, a subject of the Queen of Great Britain, residing at Portreath, Illogan, in the county of Cornwall, England, have invented certain new and ,useful Improvements in and Relating to Rock-Drills, of which the following is a specification.

This invention relates to improvements in and relating to the kind of rock-drill described in the specification of United States Patent No. 621,271, of 1899.

The invention has for its object the more eflicient working of the distributing-valve According to the said prior specification the fluid-pressure-distributing valve has a rocking motion and is actuated by a wing or vane working fluid-tight in a suitable chamber. The arrangement is such that as the piston of the drill travels to and fro it covers and uncovers suitable subsidiary ports and passages in the drill-casing, thereby admit- I ting motive fluid alternately to opposite sides of the wing or vane and so causing the latter to swing from side to side and operate the valve at the proper times. According to this invention, instead of delivering the motive fluid onto the top of the distributing-valve, as in the aforesaid specification, the said fluid is admitted at one end of the valve and passes longitudinally through a suitable passage in the body thereof to the working cylinder ports, thus reducing the pressure on the top of the valve, and consequently the wear on the bottom side or face thereof. I also furnish the said valve with two wings or vanes working fluid-tight in suitable recesses in the wall of the valve-chest, (instead of one, as in the aforesaid specification,) whereby the rocking movement is imparted thereto. These wings are operatedby the motive fluid,the admission and exhaust of which is controlled by the drill-piston, and passages are formed in the valve which put the sides of each one of the recesses or chambers in which the said wings work in communication ,respectively,with the opposite sides of the other recess or chamber, so as to enable the actuating fluid to act upon opposite faces of the two wings simultaneously. 1' also form a circular recess at that end of the distribution-valve at which the actuating fluid is admitted, in order to keep the said valve in correct position when working with the drill at an angle,and I pivot the opposite end of the said valve on a conical pivot, in order to take up wear.

In orderthat my invention may be clearl understood and readily carried into effect, will proceed to describe the same more fully, with reference to the accompanying drawings, in which- Figure 1 is a plan, and Fig. 2 is a side elevation, of that part of a rock-drill to which my invention refers. Fig. 3 is a cross-section on line A A, Fig. 1. Fig. 4 is a-section on line B B, Fig. 3. Fig. 5is a section on line 'C C, Fig. 3. Fig. 6 is a section on line D D, Fig. 3. Fig. 7 is a section on line EE, Fig. 3. Fig. 8 is a sect-ion on lineF F, Fig. 5.

a is the distributing-valve, provided with a longitudinal inlet-port a and exhaust-ports a a The ports a ct lead to the exhaustoutlet j. j

b h are vanes or wings formed on opposite sides of the valve a, and b b are fluid-tight chambers or recesses in the valve chest or casing in which the wings I) h respectively oscillate.

c c are passages which cross one another and pass transversely through the valve a, soas to connect the chambers or recesses Z2 b in such manner that the motive fluid is permitted to act simultaneously upon one side of one wing Z2 and upon the opposite side of the other wing Z).

Z1 b are blocks or buffers adapted to slide, respectively, in fluid-tight recesses b b in the drill-casing. The ends of these buffers or blocks b b at one extremity are reduced, so as to form the shoulders b -b These reduced ends of the buffers project a short distance into the wing-chamber b and are normally retained in this projecting position by the springs l) b. The aforesaid shoulders on the buffers engage with corresponding projections in the drill-casing to prevent the said buffers projecting too far into the win g-chamber b b b are annular passages respectively surrounding the buffers b b b b are passages in the buffers b b respectively connecting the annular passages 11 b with the wing-chamber Z2 cl (1 are passages in the drill-casing respectively connecting the annular passages b with the drill-cylinder.

e'is an annular recess formed in one end of the valve a for the purpose of permitting the fluid-pressure to act lengthwise upon the valve, and thus maintain the said valve in its correct position when working with the drill at an angle.

f is a conical socket formed in the opposite end of the valve a, and f is a conical pivot engaging with the socket f, the construction of this pivot and socket being adapted to take up wear.

h is the drill-cylinder.

t' is the drill-piston, provided with a central annular space 1'.

j is an exhaust-passage leading from the cylinder h to the exhaust-outlet].

7t 7c are passages leading from the distributing-valve chamber to the respective ends of the drill-cylinder.

W Vhen the drill is in operation, the valve a opens one passage to the fluid-pressure by means of the port a, while it puts the other passage 70 to exhaust by means of one of the ports a and thus causes the drill-piston to reciprocate in a manner that is well understood. As the piston i nears the end of its stroke it uncovers one of the passages d to the fluid-pressure in the eylin der h and opens the other passage 01 to the exhaust-passage j through the annular space '5, thus admitting fluid-pressure to one side of the chamber or recess 19 and putting the opposite side of the said chamber to exhaust. As the passages c 0 connect the opposite sides of the chambers or recesses Z) b as aforesaid, the opposite sidesof the said chambers or recesses b 11 are simultaneously opened to fluid pressure and exhaust. The motive fluid is thus permitted to act simultaneously upon one side of one wing I) and upon the opposite side of the other wing b,while the other sides of these wings are put to exhaust, thereby reversing the distributing-valve and balancing the pressure of the motive fluid acting on the top and bottom parts of the said valve and also holding the said valve to its face. As the valve oscillates the lower wing 12 alternately strikes the ends of the spring-buffers Zr' b, and the valve is thus cushioned and hammering is prevented.

What I claim is 1. In a rock-drill the combination with the cylinder and valve-chest, of a rotary distributing-valve provided with a central longitudinal inlet-port coincident with its axis of rotation and into one end of which the motive fluid enters, and exhaust-ports formed in said valve at opposite sides of its said central longitudinalinlet-port,substantiallyas described for the purpose specified.

2. In a rock drill the combination with the cylinder and valve-chest, of a rotary distributing-valve provided with a central longitudinal inlet port coincident with its axis of rotation and into one end of which the motive fluid enters, and with exhaust-ports formed within the body of said valve at opposite sides of its said central longitudinal inlet-port, and means for maintaining said valve in its correct position when working at an angle, substantially as described for the purpose specified.

3. In a rock-drill, the combination with a cylinder, and a drill-piston, of a valve-chest having a longitudinal valve-receiving bore and a lateral wing-chamber leading from the latter, a rotary distributing-valve provided with a central longitudinal inlet-port coincident with its axis of rotation and into one end of which the motive fluid enters, a lateral port from said longitudinal port to convey the motive fluid to the cylinder, a wing extending from the body of the valve into said wing-chamber,and exhaust-ports formed within the body of said valve at opposite sides of its said central longitudinal port, substantially as and for the purpose specified.

4. In a rock-drill the combination with the cylinder and valve-chest, of a rotary distributing-val ve provided with a central longitudinal inlet-port, exhaust-ports on either side of said inlet-port, and an annular recess at the fiuid-pressure-inlet end which annular recess communicates with the said inlet-port; and a conical pivot onthe valve-casing engaging with a corresponding recess in that end of the distributing-valve which is remote from the fluid-pressure inlet,substantially as described for the purpose specified.

5. In a rock-drill, the combination with a cylinder, and a piston therein of a valve-chest having a valve-receivin g bore, and fluid-tight lateral win g-chambers leading from said bore, a rotary distributing-valve constructed with opposite wings, a central longitudinal inlet port coincident with its axis of rotation and into one end of which the motive fluid enters, and exhaust-ports formed within the body of said valve at opposite sides of its said central longitudinal inlet-port, substantially as and for the purpose specified.

6. In a rock-drill, the combination of a ro tarydistributing-valve, wings or vanes on opposite sides of said valve, a casing for said valve having fluid-tight recesses or chambers in which said'wings oscillate, means whereby the opposite sides of said wings are alternately opened to the fluid pressure and exhaust by the working piston, and spring-buffers for cushioning said wings, substantially as de scribed.

7. Ina rock-drill the combination of a rotary distributing valve having transverse crossed passages therein, wings or vanes on opposite sides of said valve, a casing for said valve having fluid-tight recesses or chambers in which said wings or vanes oscillate and the sides of each one of which chambers or recesses are respectively connected with the opposite sides of the other chamber or recess by the said crossed passages in the valve, a WOIk ing cylinder provided with a central passage leading to the exhaust and side passages which passages is open to the fluid-pressure in the cylinder, substantially as described for the purpose specified.

8. In a rock-drill the combination of a rotary distributing-valve provided with a central longitudinal inlet-port, an exhaust-port on either side of said inlet-port, and trans verse crossed passages; wings or vanes on opposite sides of said valve, a casing for said valve having fluid-tight recesses or chambers in which said Wings or vanes oscillate and the sides of each one of which chambers or recesses are respectively connected with the opposite sides of the other chamber or recess by the said crossed passages in the valve, means for cushioning the valve-wings, a work ing cylinder provided with a central passage leading to the exhaust and side passages which respectively connect the sides of one of the said fluid-tight recesses or chambers with the sides of the working cylinder, and a working piston provided with an annular recess for alternately putting one of said side passages to exhaust while the other of said side passages is open to the fluid-pressure in the cylinder, substantially as described for the purpose specified.

9. In a rock-drill the combination of a r0- tary distributing-valve provided with a central longitudinal inlet-port, an exhaust-port on either side of said inlet-port, transverse crossed passages, and an annular recess at the fluid-pressure-inlet end which annular recess communicates with the said inlet-port; a conical pivot on the valve-casing engaging with a corresponding recess in that end of the distributing-valve which is remote from the fluid-pressure inlet, wings or vanes on opposite sides of said valve, a casing for said valve having fluid-tight chambers or recesses in which said Wings or vanes oscillate and the sides of each one of which chambers or recesses are respectively connected with the opposite sides of the other chamber or recess by said crossed passages in the valve, springbuffers for cushioning the valve-wings provided with annular recesses and having pas sages connecting said annular recesses with one of the valve-wing chambers, a working cylinder provided with fluid-tight chambers in which said spring-buffers slide and having a centralpassage leading to exhaust and side passages which respectively connect the annular recesses in the spring-buffers with the sides of the working cylinder, and a working piston provided with an annular recess for alternately putting one of said side passages to exhaust while the other of said side passages is open to fluid-pressure in the cylinder, substantially as described for the purpose specified.

In testimony whereof I have hereunto set my hand, in presence of two subscribing witnesses, this 16th day of September, 1899.

JAMES MOOULLOCIL Witnesses:

JAMES HOLLOOOMBE, F. G. POLGLASE. 

